Copyright (c) 2016-present, RxJava Contributors.
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is
distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
the License for the specific language governing permissions and limitations under the License.
/**
 * Copyright (c) 2016-present, RxJava Contributors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is
 * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
 * the License for the specific language governing permissions and limitations under the License.
 */

package io.reactivex.internal.operators.flowable;

import org.reactivestreams.*;

import io.reactivex.*;
import io.reactivex.exceptions.*;
import io.reactivex.functions.Function;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.internal.subscriptions.SubscriptionArbiter;
import io.reactivex.plugins.RxJavaPlugins;

public final class FlowableOnErrorNext<T> extends AbstractFlowableWithUpstream<T, T> {
    final Function<? super Throwable, ? extends Publisher<? extends T>> nextSupplier;
    final boolean allowFatal;

    public FlowableOnErrorNext(Flowable<T> source,
            Function<? super Throwable, ? extends Publisher<? extends T>> nextSupplier, boolean allowFatal) {
        super(source);
        this.nextSupplier = nextSupplier;
        this.allowFatal = allowFatal;
    }

    @Override
    protected void subscribeActual(Subscriber<? super T> s) {
        OnErrorNextSubscriber<T> parent = new OnErrorNextSubscriber<T>(s, nextSupplier, allowFatal);
        s.onSubscribe(parent);
        source.subscribe(parent);
    }

    static final class OnErrorNextSubscriber<T>
    extends SubscriptionArbiter
    implements FlowableSubscriber<T> {
        private static final long serialVersionUID = 4063763155303814625L;

        final Subscriber<? super T> downstream;

        final Function<? super Throwable, ? extends Publisher<? extends T>> nextSupplier;

        final boolean allowFatal;

        boolean once;

        boolean done;

        long produced;

        OnErrorNextSubscriber(Subscriber<? super T> actual, Function<? super Throwable, ? extends Publisher<? extends T>> nextSupplier, boolean allowFatal) {
            super(false);
            this.downstream = actual;
            this.nextSupplier = nextSupplier;
            this.allowFatal = allowFatal;
        }

        @Override
        public void onSubscribe(Subscription s) {
            setSubscription(s);
        }

        @Override
        public void onNext(T t) {
            if (done) {
                return;
            }
            if (!once) {
                produced++;
            }
            downstream.onNext(t);
        }

        @Override
        public void onError(Throwable t) {
            if (once) {
                if (done) {
                    RxJavaPlugins.onError(t);
                    return;
                }
                downstream.onError(t);
                return;
            }
            once = true;

            if (allowFatal && !(t instanceof Exception)) {
                downstream.onError(t);
                return;
            }

            Publisher<? extends T> p;

            try {
                p = ObjectHelper.requireNonNull(nextSupplier.apply(t), "The nextSupplier returned a null Publisher");
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                downstream.onError(new CompositeException(t, e));
                return;
            }

            long mainProduced = produced;
            if (mainProduced != 0L) {
                produced(mainProduced);
            }

            p.subscribe(this);
        }

        @Override
        public void onComplete() {
            if (done) {
                return;
            }
            done = true;
            once = true;
            downstream.onComplete();
        }
    }
}